<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        function jc(n){
            j=1;
            for(let i=1;i<=n;i++){
                j=j*i;
            }
            return j;
           
        }
        console.log(jc(3));
    </script>
</head>
<body>
    
</body>
</html>